Place the beef stew meat in the bottom of the slow cooker.
Pour the red wine and beef broth over the meat.
Stir in the tomato paste, minced garlic, thyme sprigs, salt, and black pepper until the tomato paste dissolves.
Add the sliced carrots, quartered mushrooms, and pearl onions on top.
Cover the slow cooker and cook on low for 8 hours.
Remove the thyme sprigs before serving.